Oracle SQL-将结果限制为最大值[重复]

下面是如何使用MAX()…KEEP()实现这一点:

SELECT sgb_id,
       MAX (sgb_term_code_eff) max_term,
       MAX (sgb_typ_code) 
            KEEP ( DENSE_RANK FIRST 
                   ORDER BY sgb_term_code_eff DESC ) sgb_typ_code
FROM   sgb
GROUP BY sgb_id
ORDER BY 1

完整示例:

with sgb ( sgb_id, sgb_term_code_eff, sgb_typ_code ) AS 
 ( SELECT 1, 'A', 'ACODE' FROM DUAL UNION ALL
   SELECT 1, 'B', 'BCODE' FROM DUAL UNION ALL
   SELECT 1, 'Z', 'ZCODE' FROM DUAL UNION ALL
   SELECT 1, 'D', 'DCODE' FROM DUAL UNION ALL
   SELECT 2, 'A', 'ACODE' FROM DUAL UNION ALL
   SELECT 2, 'Q', 'QCODE' FROM DUAL UNION ALL
   SELECT 2, 'Q', 'QCODE' FROM DUAL UNION ALL
   SELECT 3, 'A', 'ACODE' FROM DUAL )
SELECT sgb_id,
       MAX (sgb_term_code_eff) max_term,
       MAX (sgb_typ_code) KEEP ( DENSE_RANK FIRST ORDER BY sgb_term_code_eff DESC ) sgb_typ_code
FROM   sgb
GROUP BY sgb_id
ORDER BY 1

SGB_ID                                 MAX_TERM SGB_TYP_CODE 
-------------------------------------- -------- ------------ 
                                     1 Z        ZCODE
                                     2 Q        QCODE
                                     3 A        ACODE